Soundboard



G. 0. WISMER.

SOUNDBOARD.

APPLICATION FILED AUG.2I. I918- Patented Sept. 21, 1920.

2 SHEETS-SHEET 1.

G c. WISMERI.

SOUNDBOARD.

APPLICATION FILED Aus.21. I918.

1,35 3,555. PatenteiiSept. 21,1920.

2 SHEETS-SHEET 2.

fjvwemtoz GT Ch z's/v r GEORGE C. WISMER, OF SANTA BARBARA, CALIFORNIA.

SOUNDBOARD.

Application filed August 21, 1918.

To all whom i may concern.

Be it known that I, Gnonon C. \VIsMER, a citizen of the United States, residing at Santa Barbara, in the county of Santa Barbara and State of California, have invented certain new and useful Improvements in Soundboards, of which the following is a specification, reference beinghad to the accompanying drawings.

This invention relates to certain improvements in sounding boards for pianos and it is an object of the invention to provide a deviceof this general character having novel and improved means whereby tone of the piano is materially improved.

It is also an object of the invention to provide a novel and improved sound board having a sound box or chamber secured to the rear face thereof and wherein the sound board is provided with openings in communication with the interior of or chamber. 7

A further object of the invention is to provide a novel and improved device of this general character wherein the sound box or chamber decreases in height and width in a direction lengthwise of the treble bridge with the smaller portion thereof overlying the shorter treble strings and wherein the higher and broader portion of the box or chamber overlies the longer bass string.

An additional object of the invention is to provide a device of this general character wherein the box or chamber is provided with novel and improved means whereby the same may be effectively secured to the rear face of the sound board of the piano.

The invention consists in the detailsof construction and in the combination and arrangement of the several parts of my improved sounding board whereby certain important advantages are attained and the device rendered simpler, less expensive and otherwise. more convenient and advantageous for use, as will hereinafter be more fully set forth.

The novel features of my invention will hereinafter be definitely claimed.

In order that my invention may be the better understood, I will now proceed to describe the same with reference to the accompanying drawings, wherein:

Figure 1 is a view in elevation of a sound board constructed in accordance with an emthe sound box Specification of Letters Patent.

Patented Sept. 21, 1920. Serial No. 250,837.

bodiment of my invention, the face or belly of the sound chamber or box being removed;

Fig. 2 is a view in side elevation of my improved sound chamber or box, detached;

Fig. 3 is a sectional view taken substantially on the line 33 of Fig. 1, with the face or belly of the sound chamber or box applied Fig. fl: is a sectional view taken substan tially on the line 1 of F ig. 3; and

Fig. 5 is a sectionalview taken substantially on the line 5-5 of Fig. 2.

7 As disclosed in the accompanying drawings S denotes a sounding board of a type particularly adapted for use in connection with a piano of an upright type, and in Fig. 1 the dotted line a diagrammatically indicates the treble bridge and the line 6 denotes diagrammatically the bass bridge.

C denotes my improved sound chamber or box in its entirety and which is secured to the rear face of the board S. As is particularly illustrated in the accompanying drawings my improved chamber or box is substantially pear shaped in form and comprises the side walls 1 and the outer face or belly F. The enlarged portion of the chamber or box C overlies the longer bass strings and the narrow or restricted portion of the chamber or box C overlies the shorter or treble strings. The box or chamber C is secured to the board S on a line extending entirely around a treble bridge and said bridge is substantially centrally of the chamber or box C. v

The inner marginal portion of the side wall 1 is cut away as indicated at 2 to snugly receive the outstanding reinforcing ridges 3 extending along the rear face of the board S and intermediate each pair of adjacent cut out portions or recesses 2, the inner marginal portion of the wall 1 is provided with the laterally directed and reversely disposed blocks 4 which, together with the inner edge of the wall 1 are adapted to be glued to the rear face of the sounding board S, so that the joint between the wall 1 and the board S will be airtight.

The portion 0 of the wall 1 above the treble bridge is disposed on a continuous curvature with the lower portion C thereof more abrupt than the upper portion, and the portion of the Wall 1 below the treble bridge is S'shaped. The sound board S above the lower portion'of the treble bridge is provided with the openings 5 for a purpose which is believed to be clearly apparent to those skilled in the art to whichthis invention appertains.

It is also to be noted that the side wall 1 from the smaller or apex end portion of the chamber or box 0 gradually increases in width and that the lower end portion of the wall is of a width substantially equal to twice the width of the wall at the narrow or apex portion. In practice it has been found best to have the width ofthe wall '1 of the apex portion of the chamber or box C about 5 inches wide withthe width of the wall 1 at the lower and broader portion of said box about '10 inches wide. found of best advantage to have the wall 1 It has also been about of an inch in thickness.

- Secured .to the outer marginal portion of the wall 1 is the face or belly F substantially concavo'convex with the convex face outwardly directed. It is also to be noted that the marginal portions of the'face or belly F secured to the outer edge of the wall v -1 isrounded, as indicated at a so that the formation of sharp corners is obviated.

The outer marginal portion of the side wall 1 is provided with the plurality of spaces and inwardly directed blocks, 6 which afford further means for properly securing the face orbelly F by glue tothe sidewall 1, it being'ialso understood that .the marginal .portion of the face orbelly F is glued to the .outer'edge' of thewall 1.

From the foregolng description, it is i thought to be obvious that a sounding board constructed in accordance with my invention is particularly well adapted for use by reason of the convenience and facility with which it may be assembled and operated and 7 it will also be obvious that my invention is susceptible of some change and modification without departing from the principles and spirit thereof and for this reason I do not wish to be understood as limiting myself to the precise arrangement and formation of:

the severalparts herein shown in. carrying semi pear-shaped and having one side there-1 .of open, said box being secured to the sound board with the open side thereof closely adjacent the sound board.

2. The combination with a. sound board of a piano having a plurality of openings, of a sound box gradually increasing laterally from one end of thebox to the other and having oneside thereofopen, the edges of the walls of the open side being snugly engaged and secured to the rear surface of the sound board, said board coacting with the box to close said open side and form one side of the box, whereby sound waves are admitted into the box through the openingsin the sound board. 7 7

In testimony whereof I hereunto afiix my signature in the presence of two witnesses.

' i GEORGE C. Witnesses: I e

' S. H. PHELAN, V

J J. BENTON. 

